REAL ESTATE INVESTMENTS - Schedule of Properties Acquired (Details) $ in Thousands			9 Months Ended
	Apr. 29, 2022 USD ($)	Jan. 21, 2022 USD ($) a	Sep. 30, 2022 USD ($) ft²	Sep. 30, 2021 USD ($)	Apr. 29, 2022 ft²	Apr. 29, 2022 a
Real Estate [Line Items]
Purchase Price			$ 3,446	$ 0
Rentable area (in square feet) | ft²			13,664,209
Land | 631 Park Avenue
Real Estate [Line Items]
Rentable Square Feet/Acres | a		3.3
Purchase Price		$ 3,650
Land | 3151 Market Street
Real Estate [Line Items]
Rentable Square Feet/Acres					0.8	0.8
Purchase Price	$ 27,349
Lease agreement term	99 years
Prepaid rent	$ 19,500
Rentable area (in square feet) | ft²					500,000
Land | Schuylkill Yards Project
Real Estate [Line Items]
Rentable area (in square feet) | ft²					200,000
Operating lease costs, capitalized	$ 7,800